package com.jianhua.appmarket.common.config;

import com.auth0.jwt.JWT;
import com.auth0.jwt.JWTVerifier;
import com.auth0.jwt.algorithms.Algorithm;
import com.auth0.jwt.exceptions.JWTDecodeException;
import com.auth0.jwt.exceptions.JWTVerificationException;
import com.jianhua.appmarket.common.anno.UserToken;
import com.jianhua.appmarket.common.exception.TokenTimeoutException;
import com.jianhua.appmarket.common.util.JWTUtil;
import com.jianhua.appmarket.module.entity.system.User;
import com.jianhua.appmarket.module.service.system.impl.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Method;
import java.util.Objects;

public class AuthenticationInterceptor implements HandlerInterceptor {

    @Autowired
    UserService userService;

    @Override
    public boolean preHandle(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, Object object) throws Exception {
        String token = httpServletRequest.getHeader("token");// 从 http 请求头中取出 token
        HandlerMethod handlerMethod = (HandlerMethod) object;
        Method method = handlerMethod.getMethod();

        if (method.isAnnotationPresent(UserToken.class)) {
            UserToken userToken = method.getAnnotation(UserToken.class);
            if (!userToken.required()) {
                return true;
            }
        }else {
            // 执行认证
            if (Objects.isNull(token)) {
                throw new TokenTimeoutException();
            }
            // 获取 token 中的 user id
            String userId;
            try {
                userId = JWT.decode(token).getAudience().get(0);
            } catch (JWTDecodeException j) {
                throw new TokenTimeoutException();
            }
            //User user = userService.findUserById(Long.valueOf(userId));
            //if (Objects.isNull(user)) {
                //throw new RuntimeException("用户不存在，请重新登录");
                //throw new TokenTimeoutException();
            //}
            //验证 token
            JWTVerifier jwtVerifier = JWT.require(Algorithm.HMAC256(JWTUtil.SECRET)).build();
            try {
                jwtVerifier.verify(token);
            } catch (JWTVerificationException e) {
                throw new TokenTimeoutException();
            }
        }
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest httpServletRequest,
                           HttpServletResponse httpServletResponse,
                           Object o, ModelAndView modelAndView) throws Exception {

    }

    @Override
    public void afterCompletion(HttpServletRequest httpServletRequest,
                                HttpServletResponse httpServletResponse,
                                Object o, Exception e) throws Exception {
    }
}